Efforts have hitherto been made to provide golf balls with a multilayer structure so as to increase the distance traveled by the ball and enhance the feel of the ball at impact. In order to lower the spin rate, increase the initial velocity and further improve the feel at impact, various golf balls with multilayer structures of three or more layers have subsequently been described as well.
Golf balls having a somewhat soft cover, an intermediate layer made of an ionomer material that is relatively hard compared with the cover, and a solid core with a one- or two-layer structure that is made of a rubber material are currently in wide use among professional golfers and skilled amateur golfers as balls endowed with both excellent flight performance and excellent controllability. Such balls exhibit a high controllability in the short game because of the somewhat soft cover. In addition, owing to the combination of this cover with, on the inside thereof, a hard, high-resilience layer made of an ionomer material, such balls also suppress excessive spin on full shots with a driver and exhibit a high rebound.
Various balls of this type have hitherto been disclosed in, for example, U.S. Pat. Nos. 6,071,201, 6,254,495, 6,271,296, 6,394,912, 6,431,998, 6,605,009, 6,688,991, 6,756,436, 6,824,477, 6,894,098, 6,939,907, 6,962,539, 6,988,962, 7,041,009, 7,125,348, 7,157,512, 7,230,045, 7,285,059, 7,641,571 and 7,652,086, JP-A 2012-40376, JP-A 2012-45382 and U.S. Pat. No. 7,648,427.
In this way, there exists among professional golfers and skilled amateurs a strong demand for golf balls which enable such golfers to achieve a performance in keeping with their own level of skill. Developing a golf ball endowed with a flight performance, controllability and durability capable of satisfying larger numbers of golfers is thus important for expanding the golfer base.